#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define REP(i, n) for(int(i)=0;(i)<(n);++(i))
#define in(T,V) T V;cin>>V;

int main(){
    in(int,N);
    ll a[55];
    REP(i,N) cin >> a[i];
    cout << a[N-1] << "/" << a[0] << endl;
}